I agree w/ all that Drpank said above, except that I would advise the OP to consider a couple of things. It is equally important to (1) drive (accelerate) a platter to the right speed, then to (2) maintain it at that speed, and finally to (3) minimize or eliminate friction and other force that will slow or alter the platter speed.
Most turntable designs do a pretty good job at this, some better and some worse. Some are subject to mechanical interference and some to electronic (ex. inexpensive DD decks).
In my experience and not surprisingly, the most stable systems have been those which utilize high mass platters, often coupled to low torque motors. I have always been impressed by the Nottingham turntables for this reason, for example. Also the Acoustic Solid and some other German designs that utilize a similar design concept.
In another example, I have found that a simply replacing the ancient analog neon strobe unit in a TD-124 w/ an LED/quartz unit makes a huge improvement to the PRAT of this deck.